Information gathered by British and American intelligence agencies raises the possibility that a bomb may have brought down the Russian civilian airliner that crashed in Egypt last week. The Metrojet Airbus 321 left the Egyptian resort of Sharm el-Sheikh on Saturday, heading for St. Petersburg, Russia. But it crashed in the Sinai Peninsula less than 30 minutes after it took off, killing all 224 passengers and crew onboard, the vast majority of whom were Russian citizens.

Earlier this week, Russian airline Kogalymavia, which operated the flight, said its investigation indicated that an “external influence” was responsible for the airplane’s downing. On Wednesday, the British government appeared to confirm the company’s suspicions. Britain’s Secretary of Foreign Affairs, Philip Hammond, told a press conference in London that the British government’s Crisis Response Committee had concluded that there was “a significant possibility that the crash was caused by an explosive device on board the aircraft”. He added that Whitehall was suspending effective immediately all flights operated by British carriers to and from Sharm el-Sheikh.

Soon after Hammond’s comments, the Associated Press quoted an unnamed American government official saying that the US had reached the “tentative conclusion” that Islamist militants in Sinai were responsible for planting the bomb on the Kogalymavia airplane. The Americans seem to have reached this conclusion based on intercepted communications messages from the Sinai region.

Egyptian officials have rejected claims that Islamist militants were behind the plane crash, and have criticized London’s decision to suspend all flights to and from Sharm el-Sheikh as unnecessary and premature. Experts in Russia have also said it is too early to draw formal conclusions about the crash. Meanwhile, the airplane’s flight data recorder has been recovered and will be analyzed by investigators in the coming days.